What is tetanus?
Tetanus, or lockjaw, is an often-fatal disease caused by a neurotoxin produced by the bacteria Clostridium tetani. C. tetani is present in the gastrointestinal tracts and feces of horses and other animals. C. tetani spores can be found in soil everywhere but are particularly abundant in areas where the soil is contaminated with manure.
The C. tetani bacterium produces the potent toxin “tetanus neurotoxin” (TeNT). TeNT causes spasmodic paralysis due to inhibition of neurotransmission (signalling) between the spinal cord and neurons. Horses, regardless of breed, age, or sex, are more susceptible to tetanus than any other domestic animal.
How is tetanus in horses contracted?
Tetanus is not contagious and cannot be spread between horses, or between horses and people. Horses develop tetanus when the spores of C. tetani gain entry to the body via puncture wounds, open wounds, crushing wounds, surgical incisions, or foal umbilici. Once in the body, C. tetani produces TeNT, causing the horse to develop tetanus.
Clinical signs and symptoms of tetanus in horses
Clinical signs of tetanus in horses can include:
Wide-based "saw horse" stance
Hypersensitivity to stimuli
(light and sound)
Difficuly urinating and defecating
(including muscles of the jaw—"lockjaw")
Inability to walk
Prevention and treatment of tetanus in horses
Tetanus in horses is typically fatal. Prevention of tetanus is essential and lies in vaccination. As all horses are susceptible to tetanus, the tetanus vaccine is considered the most basic equine vaccine and is indicated in the vaccination protocol for all horses. The AAEP recommends tetanus as a core vaccination.